肺动脉灌注抗肿瘤坏死因子-α抗体减轻体外循环的肺损伤

Intra-pulmonary Artery Infusion of Antitumor Necrosis Factor-α Antibody Attenuates Lung Injury after Cardiopulmonary Bypass

目的 探讨经肺动脉灌注抗肿瘤坏死因子-α抗体（TNF-αAb）对体外循环（CPB）肺损伤的保护作用及机制。 方法 健康新西兰大白兔40只，体重2.0～2.5 kg，雌雄不拘，随机分为4组，每组10只。Ⅰ组：CPB ＋单纯肺动脉灌注液；Ⅱ组：CPB ＋肺动脉灌注TNF-αAb；Ⅲ组：单纯CPB组；Ⅳ组：单纯开胸。测定4组CPB前、后左、右心房血液中性粒细胞计数、肿瘤坏死因子-α （TNF-α）、丙二醛（MDA）含量及氧合指数；取肺组织样本，在光学显微镜和电子显微镜下观察其病理变化和超微结构改变，并动态观察肺组织含水量、TNF-α mRNA表达及凋亡指数变化。 结果 与Ⅳ组比较，CPB后Ⅰ～Ⅲ组血浆中性粒细胞计数、TNF-α、MDA含量、肺组织TNF-α mRNA表达、凋亡指数均显著升高（P＜0.05）；肺组织含水量增加，而氧合指数显著下降（P＜0.05），肺组织病理形态学发生改变。与Ⅱ组比较，CPB后Ⅰ组、Ⅲ组血浆TNF-α含量显著升高［主动脉开放5 min： （220.43±16.44） pg/ml vs. （185.27±11.78） pg/ml，P＜0.05； （249.99±14.09） pg/ml vs. （185.27±11.78） pg/ml，P＜0.05］，凋亡指数均显著升高（CPB停止即刻：60.7‰±13.09‰ vs. 37.9‰±7.78‰，P＜0.05；59.6‰±7.74‰ vs. 37.9‰±7.78‰，P＜0.05），血浆中性粒细胞计数、MDA含量、肺组织TNF-α mRNA表达亦显著升高（P＜0.05），肺组织含水量增加，而氧合指数显著下降（P＜0.05），肺组织病理形态学改变明显。与Ⅰ组比较，Ⅲ组上述指标仅在CPB30 min显著升高（P＜0.05），氧合指数显著下降（P＜0.05）。 结论 TNF-αAb经肺动脉灌注可明显抑制CPB期间炎性肺损伤，并减少肺组织细胞凋亡的发生。

Objective To investigate the protective effects of antitumor necrosis factor-α antibody （TNF-αAb） on lung injury after cardiopulmonary bypass （CPB） and their mechanisms. Methods Forty healthy New Zealand white rabbits，weighting 2.0-2.5 kg，male or female，were randomly divided into 4 groups with 10 rabbits in each group. In groupⅠ，the rabbits received CPB and pulmonary arterial perfusion. In group Ⅱ，the rabbits received CPB and pulmonary arterial perfusion with TNF-αAb. In group Ⅲ，the rabbits received CPB only. In group Ⅳ，the rabbits only received sham surgery. Neutrophils count，TNF-α and malondialdehyde （MDA） concentrations of the blood samples from the left and right atrium as well as oxygenation index were examined before and after CPB in the 4 groups. Pathological and ultrastructural changes of the lung tissues were observed under light and electron microscopes. Lung water content，TNF-α mRNA and apoptoticindex of the lung tissues were measured at different time points. Results Compared with group Ⅳ，after CPB，the rabbitsin group Ⅰ to group Ⅲ showed significantly higher blood levels of neutrophils count，TNF-α and MDA（P＜0.05），higherTNF-α mRNA expression，apoptosis index and water content of the lung tissues （P＜0.05），and significantly lower oxyg-enation index （P＜0.05） as well as considerable pathomorphological changes in the lung tissues. Compared with group Ⅱ，after CPB，the rabbits in groups Ⅰ and Ⅲ had significantly higher blood concentrations of TNF-α （5 minutes after aortic declamping，220.43±16.44 pg/ml vs.185.27±11.78 pg/ml，P＜0.05；249.99±14.09 pg/ml vs.185.27±11.78 pg/ml，P＜0.05），significantly higher apoptosis index （at the time of CPB termination，60.7‰±13.09‰ vs. 37.9‰±7.78‰，P＜0.05；59.6‰±7.74‰ vs. 37.9‰±7.78‰，P＜0.05），significantly higher blood levels of neutrophils count and MDA （P＜0.05），significantly higher TNF-α mRNA expression and water content of the lung tissues （P＜0.05），and significantly loweroxygenation index （P＜0.05） as well as considerable pathomorphological changes in the lung tissues. Compared with groupⅠ，rabbits in group Ⅲ had significantly higher above parameters （P＜0.05） but lower oxygenation index （P＜0.05） only at 30 minutes after the start of CPB. Conclusion Pulmonary artery perfusion with TNF-αAb can significantly attenuate inflammatory lung injury and apoptosis of the lung tissues during CPB.